1. Field of the Invention
The present invention relates to a tiller handle assembly for operating an outboard motor, and more specifically to a tiller handle assembly for an outboard motor having a neutral switch mounted inside.
2. Description of the Related Art
Japanese Patent Publication No. Hei 10-218088 discloses an outboard motor with an engine, which is conventionally mounted to the stem of a small boat. Steering the watercraft is typically accomplished by turning the outboard motor. To control movement of the outboard motor, the watercraft can include a steering wheel and/or the outboard motor can include a tiller arm. The steering wheel is usually positioned in front of the operator's seat, and the tiller arm has a rod shape that is directly connected to the outboard motor. An operator operates the steering wheel or tiller arm to cause the outboard motor to swing toward the port or starboard sides to change the direction in which the boat moves.
Controlling functions such as shifting and accelerating are commonly accomplished by either a remote controller or by controls located on the tiller arm of the outboard motor. The tiller arm extends from the outboard motor, while the remote controller is disposed near an operator's seat (usually at a side of the operator's seat) in the boat. The controls, which are disposed at either of these locations, commonly include an operator to shift the outboard motor among operational modes (e.g., forward, neutral, and reverse) and an operator to control engine speed (and hence the propulsion thrust). In some applications, these operators are combined together (e.g., a single lever on a remote control unit).
In applications that use a shift lever, the shift lever is pivoted forward from a neutral position to a forward position to engage the engine with the propeller and to cause the propeller to rotate in a direction propelling the boat forward. To propeller the boat in reverse, the shift lever is pivoted rearward from the neutral position to a reverse position to engage the engine with the propeller and to cause the propeller to rotate in an opposite direction.
In this type of small boat, a neutral switch is commonly used to prevent starting the engine when the shift lever is at its forward or reverse position. The neutral switch detects the position of the shift lever and allows a start motor of the engine to operate only when the shift lever is at its neutral position. In the case of an outboard motor in which shift control of the engine is accomplished by a remote control (shift lever) at a side of the operator's seat away from the stem, the neutral switch is usually disposed in a remote controller. In applications where a tiller arm is used, the neutral switch is disposed within a cowling of the outboard motor.
Japanese Patent Publication No. 2000-272588 discloses an example of a tiller handle assembly for an outboard motor. The tiller handle assembly is attached to the outboard motor depending on user's needs. The outboard motor is rotated about a swivel shaft for steering with such tiller handle assembly. The tiller handle assembly has a steering handle body of a rod shape that is pivotally connected to the outboard motor and extends generally horizontally toward the inside of the boat. A throttle grip is attached to the front end of the steering handle body and is rotatable about its axis. Turning the throttle grip about the axis of the steering handle body controls opening and closing of a throttle valve and, hence, engine speed. Additionally, a shift lever, as described above, is attached to the tiller handle assembly.
As noted above, in applications employing a tiller handle assembly with a shift lever, the neutral switch is conventionally mounted to a shift mechanism located in the cowling of the outboard motor. Because the exact application of the outboard motor is not known at the time of its assembly, the tiller handle assembly is usually attached after the outboard motor has been shipped from the manufacturers factory. Accordingly, an after-factory worker (e.g., a dealer mechanic) typically installs the neutral switch within the outboard motor cowling.
Mounting the neutral switch to the outboard motor later and then wiring, however, is very complicated and troublesome work. Further, since the neutral switch is mounted to the completed outboard motor shipped from a plant, by a distributor or a user, mounting quality is less uniform than would it be if assembled during the production processes at the plant. Furthermore, the neutral switch mounted to the outboard motor has a different configuration from the neutral switch disposed in the remote control. This requires two types of neutral switches: one type for the remote control and one type for the outboard motor.
Additionally, because the outboard motor cowling is provided with an air intake for drawing air into the engine, some water typically enters inside of the outboard motor cowling. Thus, to mount the neutral switch in the outboard motor, the switch is required to be waterproof, resulting in a complicated structure and cost increase. In particular, a shift link mechanism, which is used to shift the operational mode of the outboard motor among forward, reverse, and neutral modes, is located at a lower portion in the cowling. Thus, the neutral switch for detecting the neutral position through operation of the shift link mechanism is also located adjacent to the shift link mechanism at the lower portion in the cowling. Water, which enters the inside of the cowling, tends to collect at the lower portion in the cowling. This requires a waterproof configuration, such as making the neutral switch itself waterproof or covering it with a waterproof cover. Either approach, however, increases cost and complicates the retrofit of the neutral switch onto the outboard motor.
A need therefore exists for an improved neutral switch for use a tiller handle assembly.